Last year, cloud backup service Backblaze crunched statistics about which makes and models of the tens of thousands of drives humming away in its data centers held up best under stress. Hitachi and Western Digital came out at the top; Seagate, not so much.
Now Backblaze is back with another year's worth of stats, harvested from the consumer-level drives running in its custom-designed and open-sourced Storage Pod drive racks. The results, assembled from a data set more than twice as large as the previous year's, square with the earlier findings.
Hitachi
(now HGST, a subsidiary of Western Digital) has the lowest failure
rates across the makes and models surveyed. Western Digital itself came in second, with numbers only slightly less impressive than HGST's. "It’s
hard to beat the current crop of 4TB drives from HGST and Seagate,"
Backblaze said in its blog post.
Hard drive failures by the manufacturer over the course of one year.
HGST, a Western Digital subsidiary did best, but stats on WD's 6TB The driveline remains preliminary. Seagate, on the other hand, is another story. Its drives didn't do well in the first roundup and this year sported failure rates as high as 43 percent annually. As with last year,
its 4TB models were far more durable than its other offerings, failing at around half the rate of the previous year.
What
constitutes a failure to Backblaze? Aside from obvious mechanical
problems -- the drive won't spin up or be recognized by the OS --
Backblaze included any drives that would not sync properly with a RAID
array or reported SMART statistics that were out of the acceptable
range. This last criterion can be tricky; Backblaze itself notes that SMART stat reporting isn't consistent between
many drives. That said, the company believes a handful of the most
critical criteria, such as the uncorrectable error count or the count of
reallocated sectors are reliable indicators of failure based on what
it's seen in its drive pools.
The
best results were with 4TB drives, which showed a marked decline in failure rates since the previous year's statistics -- both between HGST
and Seagate. However, 3TB drive was less impressive, and Backblaze promised to dig into the story behind Seagate's striking failure rates there in a future post. Western Digital had no 4TB drives in the
running, but Backblaze used 6TB drives from the company's line, the
Western Digital Red. Its failure stats were less than 5 percent for the course of the year, but Backblaze cautioned it hasn't been using them for long enough to compute robust failure statistics.
Western
Digital acquired Hitachi's hard drive business and turned it into HGST
back in 2012; it was originally created in 2003 when IBM and Hitachi
merged their hard disk manufacturing concerns. The HGST drives profiled
in Backblaze's analysis were all Deskstar or Megascale models,
the latter composed of 4TB drives designed for "low application
workloads that operate within 180TB per year." Other drives in HGST's the lineup includes helium-filled 8TB and 10TB drives, with the helium providing greater capacity and lower power consumption, although
Backblaze hasn't used those drives in its tests, preferring instead to
stick with low-cost consumer drives purchased in bulk.
Backblaze
has been using its data center as a source of eye-opening and sometimes
hotly contested insights. Not long after its 2014 hard-drive
reliability report, the company analyzed the effect of cooling on drive
lifetimes. It found that keeping a drive cooler than its recommended
operating temperature had no discernible effect on its longevity. Not everyone agreed with the conclusions, but few could find fault with Backblaze's underlying mission.
For
those who want to crunch the numbers themselves, Backblaze plans to
make available the raw data from the 2014 drive pool study in the next
couple of weeks, along with more details on how it computed failure
rates.
Hello, my name is Mohd Azahar. I'm a self-employed Pivrate from the India.
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